Wet pipe pressure tank sprinkler system



Nov. 22, 1955 Filed Aug. 5, 1953 Sheets-Sheet 1 INVENTOR.

HA REY N. RIDER A 77 0 NE) Nov. 22, 1955 H. N. RIDER 2,724,444

WET PIPE PRESSURE TANK SPRINKLER SYSTEM Filed Aug. 5, 1953 I5 Sheets-Sheet 2 Eg] E INVENTOR. HA RRY N. RIDER ATT NE'V Nov. 22, 1955 H. N. RIDER 2,724,444

WET PIPE PRESSURE TANK SPRINKLER SYSTEM Filed Aug. 5, 1953 3 Sheets-Sheet 5 INVENTOR. HARRY N. E/DER MQZ/ p of the sprinkler system.

United States Patent Ofifice 2,724,444 Patented Nov. 22, 1955 2,724,444 WET PIPE PRESSURE TANKSPRINKLER SYSTEM Harry N. Rider, Youngstown, Ohio, assignor to Automatic Sprinkler Corporation of America, Youngstown, Ohio, a corporation of Delaware Application August 5, 1953, Serial No. 372,557

2 Claims. (Cl. 169-9) This invention relates to sprinkler systems and more particularly to a pressure tank sprinkler system wherein liquid in the pressure tank is expelled through sprinkler of a wet pipe pressure tank sprinkler system which is actuated by the opening of a normally closed sprinkler thereon.

A still further object of the invention is the provision of a wet pipe pressure tank sprinkler systemproviding a source of fire extinguishing liquid and automatically actuated means for discharging the said fire extinguishing liquid therefrom.

A still further object of the invention is the provision of a wet pipe pressure tank sprinkler system wherein means is provided for giving an alarm when the system goes into operation as in extinguishing a fire.

The Wet pipe pressure tank sprinkler system shown and described herein comprises an improvement in the art of pressure tank sprinkler systems particularly with respect to my previously issued patents, No. 2,277,873 issued March 31, 1942 and No. 2,290,358 issued July 21, 1942, wherein pressure tank sprinkler systems utilizing a com pressed gas as a liquid expelling medium are disclosed.

In the pressure tank sprinkler systems heretofore known in the art, various means have been employed for expelling fire extinguishing fluid at such time as the sprinkler system opened as in response to a fire in the area supervised. Originally, such systems were actuated by pressure generated as a result of chemical reaction taking place in the fluid supply tank. Such systems have been generally replaced by systems wherein a portion of the fluid supply tank comprises a compressed air reservoir, the air being replaced from time to time by an aircompressor usually electrically actuated. Such systems are in need of constant supervision in order to insure the maintenance of the compressed air supply in the fluid supply tank and are expensive in operation due to the necessity of frequently operating the air compressor to maintain the compressed air necessary.

As disclosed in the aforementioned patents pressure tank sprinkler systems have been lately developed wherein compressed gases, such as nitrogen, supplied in cylinder form and readily commercially available, are used to apply pressure to the. fluid comprising the supply source In such systems heretofore, the compressed gas has been maintained inthe cylinder and released into the fluid supply tank of the. sprinkler system through the operationof release mechanisms actuated either by rate-of-rise thermostatic systems separate from 2 the sprinkler system itself or by vacuum or suction creating devices aflixed to a high point on the distribution system of the wet pipe sprinkler system so that the drop of head in the distributing piping of the sprinkler system would create a suction which in turn would operate a release and thereby place the tank of compressed gas in communication with the fluid supply tank of the sprinkler system. Such devices, while generally dependable, are subject to the irregularities which may exist in the actuating devices and the pressure tank sprinklersystems using the same are thereby not capable of operation at such times as the said controlling devices fail to operate.

The present disclosure relates to a wet pipe pressure tank sprinkler system wherein all such controlling devices are eliminated and a cylinder or cylinders of compressed gas, such as nitrogen, is placed in direct communication through a suitable pressure regulator with a supply tank filled with fire extinguishing fluid such as water. The supply tank is directly connected through an orifice in its lowermost portion with the distributing piping of the sprinkler system which is in turn filled with fire extinguishing fluid such as water or an aqueous calcium chloride solution if the same is to be protected from freezing. Normally closed, fusible sprinklers are positioned on the distributing piping and the system operates by the fusing of any of the sprinklers which, upon opening, permits the compressed gas from the cylinder or cylinders employed to displace the fluid in the supply tank thereby discharging the fluid through the distributing piping and the open sprinklers.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being the intention to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention is illustrated in the accompanying drawing, wherein:

Figure 1 is an end elevation of the wet pipe pressure tank sprinkler system.

Figure 2 is a side elevation of the wet pipe pressure tank sprinkler system with parts broken away.

Figure 3 is an enlarged detail of a portion of the with fluid and comprising a supply source for the disfl tributing system. The supply tank is indicated by the numeral 10 and the distributing piping by the numeral 11. The distributing piping 11 communicates with the supply tank 10 through a fitting 12 in the bottom of the tank 10 defining an orifice therein. A T fitting 13 is positioned in the distributing piping 11 adjacent the fitting 12 and communicates by way of a tubular connection 14 with a valved drain line 15 and a valved fluid supply line 16. The valved fluid supply line 16 is provided with a check valve 17 so that back flow from the supply tank 10 to the valved fluid supply, line 16 is prevented. The valved drain line 15 is normally closed.

Positioned in the distributing piping 11 adjacent the supply tank 10 there is a gate valve 18?, an alarm check valve 19, a T fitting 20, and a check valve 21. The T fitting 20 provides for a fire department connection with the distributing piping 11 above the alarm check valve 19. v t

A T fitting 22 in the distributing piping 11 above the check valve 21 establishes communication between the distributing piping 11 and a drain line 23. It will be observed that another connection 24 is in communication Withthe T fitting 22, as bestshown in Figure l of the drawings, and is equipped with a valve 25 so that the distributing piping 11 above the check valve 21 may be filled with a non-freezing, aqueous, calcium chloride solution by pumping the same into the distributing system 11 at this point. The drain line 23 is also in communication with the alarm check valve 19 by way of a valved tubular member 26, the outlet thus provided being normally closed;

Still referring to Figures 1 and 2 of the drawings it will be seenthat a valved tubular connection 27 establishes communication between the alarm check valve 19 and the clapper controlled alarm valve outlet thereof with a sprinkler alarm switch 28 so that at such time as the alarm check valve 19 opens, responsive to the flow of fire extinguishing fluid through the distributing piping 11, fluid will be immediately admitted to the communication line 27. and the sprinkler alarm switch 28, thereby enabling an electric circuit to be closed and a fire alarm given by means of suitable devices such as are known in theart. A restricted drain line 43 also communicates with the alarm switch 28. The distributing piping 11 extends into the area protected by the wet pipe pressure tank sprinkler system and is provided at intervals with normally closed fusible sprinklers, as known in the art, it being understood that the complete distributing piping 11 is filled with fire extinguishing fluid at all times, the fluid usually comprising water or an aqueous solution of calcium chloride to prevent freezing thereof if such precaution is necessary.

In order that the fluid normally filling the supply tank may be expelled therefrom at such time as one or more of the sprinklers on the distributing system 11 fuse and open thereby permitting fluid to flow from the distributing piping 11, means is provided for establishing communication between the uppermost portion of the supply tank 10 and a source of fluid pressure such as cylinders 29 of compressed gas such as nitrogen. In Figures 1 and 2 of the drawings compressed gas cylinders 29-29 areillustrated with control valves 30-30 having outlet orifices 31-31. The outlet orifices 31-31 communicate by way of tubes 32-32 with an adjustable gas pressure regulator 33, such as is known in the art, and a gauge 34.

The outlet orifice of the pressure regulator 33 is in communication with a pressure line 35 so that the compressed gas, such as nitrogen, can flow therethrough to the supply tank 10.

By referring now to Figures 1 and 3 of the drawings it will be seen that the supply tank 10 has a fitting 36 forming a means of communication between the supply tank 10 and a manifold 37 positioned on the fitting 36. The manifold 37 includes a normally closed discharge valve 38 and has two outlets 39-39 normally closed by blowoff discs 40-40. The opposite side of the safety blowoif discs 40-40 communicates with a secondary manifold 41 positioned adjacent thereto and in direct communication with a vent line 42 which provides a safety blowotf arranged to discharge at a remote location.

In operation, the supply tank 10 and the distributing piping 11 of the Wet pipe pressure tank sprinkler system is normally filled with fire extinguishing fluid as heretofore described. The valved fluid supply line 16 and valve drain lines are normally closed, the gate valve 18 being normally open and the clapper (not shown) in the alarm check valve 19 is closed and ready to open upon flow of fluid th'erethrough- The drain line 43 in communication therewith is normally closed by the valve therein. The fire department connection is also normally closed. The check valve 21 is closed and ready to open upon the flow of fluid therethrough. The valves on the drain line 23 in communication with the T fitting 22 in the distributing piping 11 are normally closed and the sprinklers on the distributing piping 11 are normally closed.

In the event of fire'in the area protected by the pressure tank sprinkler system, one or more of the sprinklers will fuse which will permit the fire extinguishing fluid in the supply tank 10 to flow through the distributing piping 11 and out through the open fused sprinklers. The flow of the fire extinguishing fluid from the supply tank 10 is occasioned by the gas pressure previously introduced thereinto through the manifold 37, the pressure line 35 and the pressure regulator 33. Compressed gas is supplied from the compressed gas cylinders 29-29, as heretofore described. Gas flows from the compressed gas cylinders 29-29 through the tubes 32-32 through the pressure regulator 33 and thence through the pressure line into the manifold 37 and hence into the supply tank 10. Thus, there is no mechanical or electrical operation upon which the wet pipe pressure tank sprinkler system is dependentand hence there is nothing to interfere in any way with the automatic operation of the pressure tank sprinkler system. At such time as one of the sprinklers opens and permits the discharge of fire extinguishing fluid from the sprinkler system, the compressed gas (such as nitrogen) in the cylinders 29-29 will replace the fire extinguishing fluid in the supply tank 10 as the water is expelled therefrom thereby.

When the sprinkler system first goes into operation as in extinguishing a fire, the alarm check valve 19 will open and a small amount of fire extinguishing fluid will flow through the tubular connection 22 to the sprinkler alarm switch 28 which will give an electric signal (audible or visible, or both) indicating the sprinkler systems operation. The alarm switch 28 may obviously be connected to a fire department signal line or other signal line, if desired. The fire extinguishing fluid flowing through the alarm check valve 19 will open the check valve 21 and flow through the distributing piping 11. The sprinkler system will therefore continue to discharge fire extinguishing fluid through the open sprinkler or sprinklers until the complete contents of the supply tank 10 has been dis charged. As pressure tank sprinkler systems are usually installed in occupancies wherein the maximum of three to five sprinklers are expected to control a fire, it will be obvious that the sprinkler system disclosed herein is quite capable of providing eflicient fire protection in such situations. It will also be obvious that the size of a supply tank 10 may be varied at will, it being only necessary to add additional cylinders of compressed gas to insure an adequate expelling. pressure at such time as the sprinkler system so provided goes into operation.

When it is desired to shut off the sprinkler system, the gate valve 18 may be closed, the fused sprinkler may be replaced with a normally closed sprinkler and the system may be refilled in the manner customary with wet pipe sprinkler systems. When the system is refilled, new cylinders of compressed gas are substituted for the exhausted cylinders and placed in communication with the fluid supply tank 10, the gate valve 18 is again opened and the sprinkler system is then ready for subsequent operation.

It will thus be seen that a simple and efiicient wet pipe pressure tank sprinkler system has been disclosed which possesses the advantage over pressure tank sprinkler systerns heretofore known in the art of a complete lack of dependence upon thermostats, suction devices, release mechanisms and the like, and is thereby always ready for operation in extinguishing a fire.

The modification of the construction disclosed herein will be apparent to those skilled in the art and one such modification of themeans of, connecting the cylinders 29-29 of compressed gas to the pressure tank 10 is illustrated in Figure 4 of the drawings. By referring thereto it will be seen that the tubing 35 communicating with the compressed gas cylinders 2929 communicates with a pressure pipe 45 which in turn establishes communication with a manifold 46.

A fitting 47 establishes communication between the manifold 46 and the pressure tank andthe manifold 46 includes a normally closed manual valve 48. Another portion of the manifold 46 communicates with an orifice 49 which is normally closed by a blowoff disc 50. The opposite side of the blowofi disc 50 leads to a vent 51 and it will be understood that the blowotf disc 50 of the modification shown in Figure 4 and the blowol'f discs 40--40 prevent rupture of the pressure tank 10 and/or the distribution piping in the event of mechanical failure of the pressure regulator normally controlling the pressure from the compressed gas cylinders 29-29.

It will also occur to those skilled in the art that a low pressure responsive switch 44 is preferably connected pendablein meeting its purpose and the several objects of the invention.

Having thus described my invention, what I claim is: 1. A wet pipe pressure tank sprinkler system comprising a liquid supply tank having a gas inlet at its top and an outlet at its bottom, a liquid supply line communicating with said tank through the bottom thereof, a distributing line leading from said outlet, a check valve in said distributing line, an alarm switch, a tube extending from said distributing line to said alarm switch whereby the switch is closed by action of liquid, flowing through the distributing line when the system is in operation, a horizontal manifold over said tank connected intermediate its length with the gas inlet of the tank, couplings at opposite ends of said manifold, a valve-controlled cylinder containing gas under pressure, a tube connecting the valve of said cylinder with the coupling at one end of said manifold, a pressure regulator in said tube, a secondary manifold disposed horizontally over the first mentioned manifold and having couplings at opposite ends disposed over the couplings at opposite ends of the first mentioned manifold, members connecting the couplings of the second mentioned manifold with the companion couplings of the first mentioned manifold each including a blowoff disc, and a vent line leading from the coupling at one end of the second mentioned manifold.

2. A wet pipe pressure tank sprinkler system comprising a liquid supply tank having a gas inlet at its top and a liquid outlet at its bottom, a liquid supply line communicating with said tank, a distributing line leading from the liquid outlet, a check valve in said distributing line, a shut-off valve in said distributing line between said tank and said check valve, an alarm switch, a tube leading from said check valve to said switch and through which liquid flows to close the switch and thereby sound an alarm when the system is in operation, a manifold over said tank connected with the gas inlet of the tank, a removable cylinder containing gas under pressure and having a valve controlled outlet at its top, a tube having one end detachably connected with the valve of said cylinder and its other end connected with an end of said manifold, a pressure regulator in said tube, a valve controlled discharge connected With the other end of said manifold, a vent pipe, and a connection between said vent pipe and said discharge including a blow-off disc.

References Cited in the file of this patent UNITED STATES PATENTS 1,006,528 Brent Oct. 24, 1911 

